The merit of this experiment depends highly on whether he's actually captured all his nutritive and caloric needs within his recipe. There are a lot of vitamins and minerals that we need, but that aren't found in that many things. We get them through diversity of diet. Vitamin B12 is a good example--it's found in meat and some types of seaweed and not much else, so vegetarians and vegans are usually deficient in it without supplementation.
Whenever you restrict your diet consistently over time like that, you run the risk of deficiency. So if you take it to the extreme of eating the exact same thing for every meal, you had better make sure that that one meal really does contain everything your body needs, or else you are going to develop a deficiency very quickly.
Whenever you restrict your diet consistently over time like that, you run the risk of deficiency. So if you take it to the extreme of eating the exact same thing for every meal, you had better make sure that that one meal really does contain everything your body needs, or else you are going to develop a deficiency very quickly.